Effects of strontium on the characteristics of Pb(Zr1/2Ti1/2)O3 - Pb(Zn1/3Nb2/3)O3 ceramics

Abstract

The dielectric and piezoelectric properties of pyrochlore-free lead zirconate titanate-lead zinc niobate ceramics were investigated systematically as a function of Sr doping. The powders of Pb(1-x)Srx[0.7(Zr1/2Ti1/2)-0.3(Zn1/ 3Nb2/3)]O3, where x = 0-0.06 were prepared using the columbite-(wolframite) precursor method. The ceramic materials were characterized using X-ray diffraction, dielectric spectra, hysteresis and electromechanical measurements. The phase-pure perovskite phase of Sr-doped PZN - PZT ceramics was obtained over a wide compositional range. The results showed that the optimized electrical properties were also achieved at composition x = 0.0, which were KP = 0.69, d33 = 670 pC N-1, Pr = 31.9 C cm-2 and rmax = 18600. Maximum dielectric constant values of the systems decreased rapidly with increasing Sr concentration. Moreover, with increasing Sr concentration dielectric constant versus temperature curves become gradually broader. The diffuseness parameter increased significantly with Sr doping. Furthermore, Sr doping has been shown to produce a linear reduction in the transition temperature (Tm) = 294.1-12.7xC with concentration (x). Sr shifts the transition temperature of this system at a rate of 12.7C mol-1%.